I'm going to make up some battery ground cables and need some advice. In the pic below the bottom cable is from the passenger side battery. There are two small wires attached to it: one goes from the battery to the fender wall, the other from the engine to the frame. Is it necessary to replace these when I make the new cable? If so, with the one that usually goes from the engine to the frame, can I run it instead from the battery to the frame? That would make it much easier to attach the connector on the engine end of the cable. Many thanks for any advice. - Brian

 

You do not want to change the ground path. They are critical and can cause ill effects if modified from the original design. You can make them separate cables, but keep them connected to the same points with the same gauge (or larger) wire. If you remove the cable from the frame to the engine, you can melt every other ground on the engine when you crank the starter as that is one less path to ground. It seems fruitless, but the grounds are pretty important in your electrical system.

 

You need to duplicate in some way what those cables do.
Even if it's a separate cable that runs between the engine, frame, body, and battery negative post.

 

Over the years, i have learned the starter loves good ground and good power connections.
When i replace ground cables, I run the cable from the battery to a bolt holding the starter on.
I also clean or replace the other ground cables

 

Thanks guys. I'll keep the ground points and run the wires to them separate from the main ground I'm replacing.

 

Knowing that they will cut a three-cent item if it's not necessary, keeping busy a team of engineers to do just that very thing, do you think Ford considers these two pigtail stubs necessary?

Hmmm......

Pop

 

Make sure you really clean all mounting point surfaces very well too. By clean I mean use sand paper. Just because they were covered with a cable lug doesn't mean they're good and clean.

 

Older thread, but these are older trucks, and the OP posted a great picture, which I'd like to utilize to ask a question to those who have Ford wiring diagrams for the 1999-2003 trucks.

I have a 2000, and as such, have a 2000 Ford Service disk (bought from Helm, Inc), which has the EVTM for wiring diagrams. These diagrams do not appear to be complete, as they do not index all the visible grounds on the vehicle.

If you have any version of Ford wiring diagrams, can you verify whether or not my annotations of the OP's photo are correct, in terms of what each ground is called? In order for other parts of the diagrams to be useful in tracing all the ground paths, I need to know their Ford names.

The following names were derived from several different data sources, covering different years between 99 and 03. The differences explain why one specific engine ground on the driver's side under the power steering pump is called three different names in as many publications.

My 2000 publication doesn't even list G106, nor does it list several other grounds that are on the vehicle. My diagrams also do not indicate wire gauge size, whereas 2003 and up diagrams do. Anyway, I need to track down all of the grounds in my truck, and get their correct names, so that when I'm reading the electrical diagrams in block form, I'll know what ground is which.

Any confirmation you can assist with will be helpful. Thanks!

 

First off, I'm NOT an electrical engineer. My feelings about the electrical systems in these trucks come from years of building computers. Voltage to different components matter!

My first encounter with an electrical issue was with my wife's Maxima. She bought one of these 8-track tape power converters that would play her mp3 player music through the radio. I rarely drive that car, so I don't know when.... but soon she informs me her air bag light is flashing. After some digging around the internet... you find that if you use this device, it will cause you air bag light to flash, as the extra voltage on that circuit causes the air bag system to read a fault, and the computer then disables it. They also found that any radio installed that drew more voltage/amps/etc?... would create the same air bag light flashing.
I've never had it happen, but you read on the forums... people who install newer headlights on older trucks.... have all kinds of weird electrical stuff start happening...
Again... its simply changing the voltage draw on a circuit built within certain limits. And I'm sure I'm using the wrong electrical terms, so don't jump me on that.
I've got a 2001... but without looking it up, lets just say I have (20) sensors. I'd guess a 2017 has 100 plus... you can change most anything electrical you want on a new truck through a computer. More sensors... more chances of screwing up a circuit is my way of thinking.
Electrical problem.... first thing in the manual.... check your grounds. PCM problems.... first thing in the manual...check your grounds... get the hint?
I changed all my old battery cables a couple of months ago with OEM cables... I figure if they last another 16 years, they'll be taking my keys away from me by then anyway, as I'll be O L D ..... BUT... those battery cables are IMPORTANT, they don't just start the truck.

BTW : Walmart sells the OEM cables online... free shipping to local store

 

Just use an OEM cable $45 and be done with it.

 

The last two responses are great advice for the OP's original question... but he hasn't responded to this thread in 5 years. That this thread was exhumed again is my fault, but it was the best way I could think of to attribute the original photo, which is the ONLY photo I've ever seen of both stock factory ground cables stretched out side by side.

I'm not trying to replace the factory ground cabling. I'm trying to determine what the grounds are called, in order to trace multi circuit ground splices on other pages of the block wiring diagrams, where the block diagram is drawn in such a way that does not provide circuit length scale, nor a location reference for the terminating ground, absent of the knowledge of what that ground is labeled as.

So that is what I'm trying to do... verify what the main grounds are called or labeled as, because I too, have experienced funky electrical behavior that likely has it's roots in grounds. Two examples come to mind:

• A friend added HID lights... first and ONLY time I've experienced a CMP failure was in his truck, soon after he added the HID lights

• I've had two partial alternator failures (1 upper, 1 lower). Both times my first and only indication of a developing fault with the alternators was my transmission acting strange. Neither time did the Battery light appear on the dash. Not once. Therefore, as far as the truck knew, the alternator was still performing as required. But in reality it wasn't, and it's ill effects were traveling through the negative ground and effecting the transmission control circuits

In the course of tracing grounds on the diagram, I've learned that the PCM actually has 4 separate ground points that are very distinct from each other in terms of what other equipment is shared on that ground circuit. PCM Circuits served by Pins 3, 23, 24, 61, 76, 77, & 103 obtain their ground through Splice S106 which leads to Ground G101. However, the circuit served by PCM Pin 33 is grounded at Ground G300, along with the case of the PCM. The circuit served by Pin 25 is grounded at G100.

Looking solely at the wires that actually attach to the grounding points themselves does NOT tell the whole story about what all is grounded at those grounds. The real story is buried deep into the harnesses, as SPLICE joints.

For example, Splice 102 is where the windshield wiper motor ground and the PCM ground for Pin 25 is bonded. We can't see this by looking at the cowl of our truck. The splice is buried inside the harness, near the takeout next to Connector C1042. This splice of the ground circuit could be where and why the CMP starts acting funny on some trucks when the intermittent setting of the windshield wipers is activated. Yet there could be other factors, as there are over a half dozen other components bonded to the same splice point (S102) that eventually come together as one wire that bonds to the body at ground G100.

We see G100 on the cowl. We can't really see S102 without knowing about it ahead of time on the block wiring diagram. On the diagram, we can see the relationship between S102 and G100, but without knowing what G100 is referring to, we don't know where to look on the truck itself. Hence, that is what I'm asking for help with... because my diagrams are a bit sketchy. The are from the Ford factory service manual suite, but they appear to not be as comprehensive as Ford has produced in later model years, or perhaps in other publications.

So, to the extent that any information you have or have access to can either confirm or correct the ground identifiers that I have superimposed on the photo above, that would be of great assistance in furthering this research on what circuits ultimately ground where. I'd appreciate your help in this!